Pilot study on the control of algal membrane fouling by preoxidation with potassium permanganate composites

An integrated process of preoxidation, coagulation, sedimentation and ultrafiltration was used to treat algae-rich water and evaluate its algae removal efficiency in pilot experiments. The mitigation and mechanism of membrane fouling by preoxidation with potassium permanganate composites (PPC) is discussed. The results showed that the average algae removal rate increased about 28% with preoxidation at a PPC dosage of 0.6 mg·L^-1. When treating algae-rich water with the integrated process, PPC preoxidation could enhance the performance of the pretreatment and control reversible and irreversible membrane fouling by reducing the foulant load on the membrane. The experiment results of chemical cleaning showed that the recovery of transmembrane pressure in alkaline cleaning was much greater than that in acidic cleaning, which indicated that the main foulants on the membrane in the ultrafiltration of algae-rich water were organics.